封面说明：甘肃晚中新世临夏鸵鸟生活环境复原图。位于青藏高原东北缘的临夏盆地，在晚中新世曾是一片开阔的稀树草原地带，大量的三趾马和临夏鸵鸟在那里繁衍生息。通过研究临夏鸵鸟的一段颈椎和气管化石，揭示出它不同寻常的生活和死亡埋藏历史。气管的切片显示出其骨化以及再改造的结构特征，具有与现代鸵鸟气管不同的生长趋势。在组织学与脱矿后的骨骼提取物中，首次发现了特异保存的血管等软组织残留；而鸵鸟化石的颈椎部分保存了大量的微生物钻孔痕迹，表明鸵鸟死后经历了强烈的微生物改造以及快速的环境变化。详见本期李志恒等人文。（绘图：郑秋旸）
Cover image：A fossil ostrich neck from Late Miocene deposits in the Linxia Basin adjacent to the Tibetan Plateau in China demonstrates extraordinary preservation and tells a story about the animal’s life and death. The ostrich trachea section preserved with several neck vertebrae is composed of bony rather than cartilaginous rings, and the bone exhibits remodeling demonstrating a different mode of growth as compared to the living species of ostrich. Histological study of the neck vertebrae reveals the soft tissue preservation of blood vessels and an ancient bacterial invasion of the bone that occurred shortly after the bird’s death. See details in the paper of Li et al. (illustrated by Zheng Qiu-Yang)
